This invention relates to an improved electrode combination that may be quickly substituted for existing electrode combinations. More particularly, this invention relates to an improved electrode holder for use with electrodes having cooling tubes internally received therein and which provides a mean for properly positioning the cooling tubes with respect to the tip of the electrode.
Electrode holders are known in the prior art and are used in many industrial application such as spot welding. The electrodes utilized with these electrode holders are often fluid cooled by an internal cooling fluid tube.
An example of a prior art electrode holder is disclosed in U.S. Pat. No. 3,215,811 in which an electrode holder receives an electrode having an internal cooling fluid tube. The cooling fluid tube is connected into fluid passages in a body portion to which the electrode holder is attached. The cooling fluid tube extends to a position within the electrode such that a lower end is spaced above the tip of the electrode by a set distance. This distance must be accurately controlled to ensure the cooling fluid tube is not positioned too close or too far from the tip. If the cooling fluid tube is positioned too far from the tip it is possible that an inadequate supply of cooling fluid will reach the tip of the electrode. If the cooling fluid tube extends to a position too close to the electrode tip, it may restrict the return flow of fluid, which is normally about the outer periphery of the cooling fluid tube. Both situations are undesirable and thus it is preferable to be able to accurately position the cooling fluid tube within the electrode at a desired distance from the electrode tip.
The prior art electrode holders do not always allow accurate positioning of the electrode with respect to the cooling fluid tube.
It is therefore an object of the present invention to disclose an electrode combination in which the electrode will be properly positioned with respect to the cooling fluid tube such that the end of the cooling fluid tube is accurately spaced from the electrode tip to ensure optimum flow of cooling fluid.
It is further an object of the present invention to disclose such an electrode holder that may be easily incorporated into existing electrode combinations.